Entering Thursday night's game against the Cardinals, the 49ers undoubtedly had the top defensive unit in the NFC, if not the entire NFL. They still can lay claim to that title, but they didn't play like it in Arizona.
Sure, San Francisco got the 28-25 win to improve to 8-0, but it certainly wasn't as commanding of a victory as any of the prior seven. The 49ers allowed a touchdown on the Cardinals' opening drive, and the defense really wore down in the second half. If not for some poor clock management on the part of Arizona coach Kliff Kingsbury, San Francisco's record might no longer be spotless.
After escaping with the victory, NBC Sports Bay Area's Donte Whitner was highly critical of the 49ers' defensive effort, particularly at the start of the contest.
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"Understanding that when you take the field early in the football game, you have to pack the defense and you have to match or exceed the intensity of the offense," the former 49ers safety urged. "So if you come out and those guys are running the football and you're flat and you're waiting on one of your teammates to make a play, this is when big plays happen. Each individual has to go out there with the mindset that 'I'm going to be the guy that makes the play, I'm not going to ease into this football game, and we're going to match or exceed the intensity of the offense.' And they didn't do that today.
"They didn't start the game fast, they didn't sustain throughout the middle of the game and they didn't finish. And you can't beat teams like the New Orleans Saints with Drew Brees, and they have a good defense. And the Green Bay Packers with Aaron Rodgers, and they have a good defense. You have to play Seattle twice, you have Baltimore ... if you play the way that you played today versus those good teams, you don't have a chance to win these games."
It's worth mentioning that San Francisco's lackluster defensive performance came on a short week, as the 49ers were playing their second game in a span of five days. Of course, so were the Cardinals.
Whitner didn't buy that as an excuse.
San Francisco 49ers
"I don't think the short week played into that at all," he said. "There were simple plays out there, like the deep over route that went for 88 yards. I guarantee you [Emmanuel] Moseley has probably covered that route a thousand times since he's been in San Francisco, a thousand times playing football in college, and then just on that play, you get stuck in between. 'Oh, do I make the tackle, or do I go for the pick?' And he chose the latter, he didn't get the football, and then they had an 88-yard play.
"And then, pursuit angles. Even once he catches that football, you have a corner on the backside in [Richard] Sherman who takes the wrong angle, overruns it, allows the guy to cut back. And then you have a middle-field safety -- whose job is last defender, get the guy on the ground -- and he overpursues and takes a bad angle. So it's not just Moseley, it's everybody. Once he catches the football, you take good angles to the football and you get the guy down. You live to play another defensive series or another play, and they didn't do that."
As Whitner pointed out, the 49ers have several high-quality opponents on their upcoming schedule, beginning in Week 9, when they host the rival Seahawks on Monday Night Football. The former safety knows just how difficult of a challenge Seattle's Russell Wilson poses, and described how San Francisco might prepare for the dynamic quarterback over the coming week.
"What they'll probably put back there is a wide receiver or somebody to emulate [Wilson] running around, breaking the pocket, plastering," Whitner explained. "Plastering is when the defensive backs have to latch onto the receivers they're covering because once he starts to scramble, the guys who go deep come back to the ball, and the guys who run short routes, they go deep. So you have to have muscle endurance to be able to cover these guys, because you have guys like Tyler Lockett, who will take off, run a 15-yard route, [Wilson] starts scrambling and he takes off 40 yards across the field.
"You have to have muscle endurance to be able to keep up with [Lockett], and if you don't do that, they can blow you out or put a blemish on this record. So you want to understand what he's doing, you want to have a sense of urgency from the defensive line to get Wilson on the ground, and not allow him to run around and throw the football."
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While Cardinals rookie quarterback Kyler Murray has a long way to go to reach Wilson's level, the No. 1 overall pick from the 2019 NFL Draft was fairly impressive against San Francisco on Thursday night, and NBC Sports Bay Area's Ian Williams believes the 49ers' experience against Murray will benefit them against Wilson next week.
"Being able to play this game today against Kyler Murray definitely helps the defense," Williams said, "because now they'll be able to go into the film room this next week, be able to watch the film and correct the mistakes, like letting Murray out of the pocket on the touchdown he threw and other instances where he was able to get outside the pocket and scramble around.
"They're going to see a lot of that this week coming up on Monday night, but I feel like seeing that now -- they don't really have that kind of guy on their roster -- they got a great look tonight, and they got the win. So now, go back, see what you did wrong, correct it, and then come out on Monday night and don't make those same mistakes."
The 49ers produced arguably their worst defensive performance of the season on short rest. They should be replenished -- and reinforced -- by Monday night, and against Wilson, they'll need to be.